This invention relates to a borehole seal, and in particular to a water activated seal.
During seismic exploration, a plurality of holes are drilled into the ground. Often the hole will flow, i.e. water will flow or seep to the surface. By law, such flowing holes must be stopped or plugged. At present, the holes are plugged by means of a device including a rubber bladder. When the device is placed in a hole and inflated using compressed air, a plug is formed. The hole is then filled with concrete to create a permanent plug. The principal disadvantage of such a system is that a specialized contractor must be employed to install the plug which can be quite expensive.
Hole seals or plugs are also required for shot holes, i.e. holes containing explosive charges used for seismic exploration. It should be possible to seal a seismic hole quickly; otherwise, exploration time may be unduly lengthy.
Applicant's Canadian patent application Ser. No. 453,879, filed May 9, 1984 describes a liquid activated seal or plug which is particularly designed for so-called flowing holes, i.e. holes containing water.
The object of the present invention is to provide an even more simple seal and hole sealing method which is particularly suitable for use in shallow boreholes such as seismic shot holes.